<template>
  <div class="wrapper" :class="toastClasses" :style="{zIndex}">
    <div class="toast" ref="toast">
      <div class="message">
        <slot v-if="!enableHtml"></slot>
        <div v-else v-html="$slots.default[0]"></div>
      </div>
      <div class="line" ref="line"></div>
      <span class="close" v-if="closeButton" @click="onClickClose">
      {{closeButton.text}}
    </span>
    </div>
  </div>
</template>

<script>
  export default {
    name: 'GuLuToast',
    props: {
      zIndex: {
        type: Number,
        default: 20
      },
      autoClose: {
        type: [Boolean, Number],
        default: 5,
        validator(value) {
          return value === false || typeof value === 'number'
        }
      },
      closeButton: {
        type: Object,
        default() {
          return {text: '关闭', callback: undefined}
        }
      },
      enableHtml: {
        type: Boolean,
        default: false
      },
      position: {
        type: String,
        default: 'top',
        validator(value) {
          return ['top', 'bottom', 'middle'].indexOf(value) >= 0
        }
      }
    },
    mounted() {
      this.updateStyle()
      this.execAutoClose()
    },
    computed: {
      toastClasses() {
        return {[`position-${this.position}`]: true}
      }
    },
    methods: {
      updateStyle() {
        this.$nextTick(() => {
          this.$refs.line.style.height = `${this.$refs.toast.getBoundingClientRect().height}px`
        })
      },
      execAutoClose() {
        if (this.autoClose) {
          setTimeout(() => {
            this.close()
          }, this.autoClose * 1000)
        }
      },
      onClickClose() {
        this.close()
        if (this.closeButton && typeof this.closeButton.callback === 'function') {
          this.closeButton.callback(this) //this ==> toast 实例
        }
      },
      close() {
        this.$el.remove()
        this.$emit('close')
        this.$destroy()
      }

    }
  }
</script>

<style lang="scss" scoped>
  $font-size: 14px;
  $toast-min-height: 40px;
  $toast-bg: rgba(0, 0, 0, 0.75);
  @keyframes slide-up {
    0% {opacity: 0;transform: translateY(100%)}
    100% {opacity: 1;transform: translateY(0%)}
  }

  @keyframes slide-down {
    0% {opacity: 0;transform: translateY(-100%)}
    100% {opacity: 1;transform: translateY(0%)}
  }

  @keyframes fade-in {
    0% {opacity: 0;}
    100% {opacity: 1;}
  }

  .wrapper {
    position: fixed;
    left: 50%;
    transform: translateX(-50%);

    &.position-top {
      top: 0;

      .toast {
        border-top-left-radius: 0;
        border-top-right-radius: 0;
        animation: slide-down 1s;
      }
    }

    &.position-bottom {
      bottom: 0;

      .toast {
        border-bottom-left-radius: 0;
        border-bottom-right-radius: 0;
        animation: slide-up 1s;
      }
    }

    &.position-middle {
      top: 50%;
      transform: translate(-50%, -50%);

      .toast {
        animation: fade-in 1s;
      }
    }
  }

  .toast {
    animation: fade-in 1s;
    font-size: $font-size;line-height: 1.8;min-height: $toast-min-height;
    display: flex;
    color: white;align-items: center;background: $toast-bg;border-radius: 4px;
    box-shadow: 0 0 3px 0 rgba(0, 0, 0, 0.5);padding: 0 16px;

    .message {
      padding: 8px 0;
    }

    .close {
      padding-left: 16px;
      flex-shrink: 0;
    }

    .line {
      height: 100%;
      border-left: 1px solid #666666;
      margin-left: 16px;
    }


  }


</style>